Originally Posted by NMGlocker
I did not know that pressure ratings were in "feet per second", I always though it was "pounds per square inch".
SAAMI pressure ratings for the 9mm are 35000 PSI for standard and 38500 for +P, there is no spec for +P+.
You don't own an ammo lab?
From your post, I could have sworn you were some kind of ballistics/physics expert.
Traditionally, pressure measurements, with regard to internal ballistics/small arms, are in CUP or Copper Units of Pressure.
That being said, while pressure affects velocity, it is not always directly proportionate.